It is established around the Caguanes peninsula and includes 10 small cays (Cayos de Piedra) that reach out in the Bay of Buena Vista (a Ramsar Convention site), as well as the Guayaberas swamps and mangroves.

[1] The coastal landscape is characterized by caves, arches and niches that open to the sea.

A large population of mariposa bats is present in the Tres Dolinas cave.

A decline in migratory aquatic birds (spoonbills, flamingos, pelicans) nesting in the marshes was registered here.

The closure of three sugar mills reduced the pollution in swamps and bay, and numbers were increasing as of 2007.